$1.2m, and Expedia now use the SeatGuru information when selling seats. As a result, SeatGuru has received some criticism for presenting seat maps which are inaccurate and for which no one from the company has travelled on the aircraft; for example, showing bars on aircraft where there are none (on the Singapore A380) or seat rows that don't exist (on the Emirates A380) or airlines that don’t exist (like Skylanes, which the website says is based in Chicago). Seat designation On many aircraft, the rightmost seats have letter designations HJK, skipping the letter I. This is because each seat has a row number followed by letter; letters that may be confused with numbers (I, O, Q, S, or Z) must be avoided, usually for people with dyslexia. The Digital Equipment Corporation (DEC) was the first to implement this, avoiding I (1), O (0) and S (5). The remaining letters are called the DEC alphabet. Some airlines may skip some letters because some of the letters are absent from their alphabet (e.g. an airline in Vietnam may have the layout ABC-DEG-HKL in economy class because letters f, j, w, and z are absent from the Vietnamese alphabet). Occasionally, aircraft with a seating structure of 2+2 may letter the seats as "ACDF" to keep with the standard of A/F being window and C/D being aisle on short-haul aircraft (which generally have 3+3 seats). In first- and business-class cabins, the seat letters for the window seats will typically be the same as in economy, with some letters skipped in between as there are fewer seats per row. For example, if economy cabin is ten across, labeled ABC-DEFG-HJK, the business-class cabin might be labeled AC-DG-HK for a six-across layout, with A-DG-K for a four-across first class. One notable exception to this is Delta Air Lines, which uses sequential letters regardless of cabin layout on all aircraft (AB-CD-EF in business class and ABC-DEF-GHJ in economy). Some airlines omit the row number 13, reputedly because of a widespread superstition that the number is unlucky. This is the case with Lufthansa, for example (as shown on the Lufthansa A321/100 seating plan). Emirates used to have a row 13, but on their latest A380 aircraft have removed it (as shown on Emirates A380-800 seating plan). British Airways is less superstitious, and their seat maps for A320 aircraft show a row 13. Delta Air Lines also includes row 13